I think it's perfectly possible to live off state pension assuming a few things... For me for example I am focussed on clearing the mortgage and my (thankfully dwindling loan balance), if that means I have only state pension in 5 years so be it.. If you are in a couple and are due to retire in a few years then state pension will be around £13k a year each. If you have no mortgage, take sensible holidays and only 1 car (that you own and is ideally cheap to run) then I simply don't see how you couldn't..
In my situation for example assuming we both retired around the same time and got SP then that would give us £26k a year combined. From this:
Bills Inc C.Tax, house insurance, energy etc would.come to around £450pm. Another £150pm to cover running a small PHEV car. Say £500pm for food and £60pm for 2 X sim only phone contracts and a basic FTTP fibre connection. Throw in £100pm for misc stuff that takes us to £1260 pm leaving £700 odd quid for whatever....
So assuming you are in a couple and both receive SP and have no mortgage you could easily do it, on your own you would get some money (pension credit, c.tax help etc) so it would be tight but still doable
I know a few people who have decent pensions but are still paying a mortgage and in 1 instance still paying rent which is mad to me.. I would rather be mortgage free / debt free with SP Vs decent pensions but still owing money..
The caveat is that you don't have a big chunk for any major unforeseen bills although if you are in a couple and live modestly I think you could save £500 a month so it would soon add up.
My grandmother lived her entire life without working.. she was the wife of a farm labourer and that was just the norm back then (to not work), she raised 2 kids and lived off state pension in a small bungalow for 15 years. She was always busy and had an active life with many friends.
When she died she had £12k in her building society savings account and a healthy bank balance.